I used to work at Accenture back when they paid workers overtime. As engagement managers got into overage (underestimated projects, often fixed fee), they would put pressure on their workers to work overtime but not log the hours. Two law firms were already reaching out to workers ~2002 trying to form a class for a class action lawsuit.

My boss came by one Friday morning and informed me i'd be onsite working all weekend and told me to "ensure not work over 40hrs" this week. This is an impossibility, I had been working late all week and was already at 45 or 50hrs for the week, and I still had Friday/Saturday/Sunday to go.

So after the discussion, I sent him an email, casual, saying I've cancelled my flight back home for the weekend, confirming i'll be onsite all weekend and that I'd ensure to "only log 40hrs this week".

He came by my desk furious and said if I "ever pulled a stunt like that again there would be consequences"

So I re-plied to the original email, took him off, put on my personal gmail and just recounted the entire episode and sent the email again.